It is previously known quick couplings for connecting high pressure lines, i.e., lines which can receive a fluid under a high pressure, such as hydraulic lines in working machines, such as tractors, bucket loaders, digging machines, bulldozers, trucks with tilting facility, forest machines, cranes and the similar, hydraulic driven units of different kinds such as control units onboard ships and aircrafts, breaking fluid lines at heavy vehicles including railroad bound vehicles, towing rolls onboard fishing ships, and many other applications where hydraulic control is suitable and is used. Normally, the hydraulic fluid, oil or water, or other suitable fluid it put under a high pressure, at least 10 kg/cm2, and usually 100-300 kg/cm2.
WO 96/35906 discloses such a quick coupling comprising a female part and a male part, whereby the male part used in said female part comprises a cylindrical part the peripheral surface of which being provided with different grooves, i.a., to receive blocking elements for efficient locking male and female parts together. Male and female parts are released from each other by moving the parts into each other above a locking position, whereby the blocking elements are released from the locking position and male and female parts can be separated from each other. At the mounting/connection of female and male parts the male part is provided with a so called mounting latch arranged to a groove in the male part, which mounting latch prevents the male part from being moved too far into the female part and thereby releasing the blocking elements at the moment of connection. The mounting latch remains in its groove after mounting to prevent the male part from being inadvertently pressed into the female part and thereby being released from this. The mounting latch, which thereby is a security latch, must, however, be eliminated before the release of the coupling, i.e., before male part and female part are to be released from each other, in order to facilitate such release. The mounting latch/security latch according to the above given patent publication is a simple U-latch being snapped over the male part in the groove intended hereto and which latch is maintained by means of the material-elasticity where it closes tight around the shaft in its groove. The latch is provided with a projection containing a recess into which a screwdriver or the similar can be introduced to withdraw or draw out the latch radially from the shaft of the male part. The latch can then easily be lost, which is a problem at maintenance in working environments where spare latches are not easily at hands. The latch is this in no way secured to the coupling and tests made connecting the latch to the male part using a thread/wire has shown that such a wire often will become a hindrance during work, whereby the latch involuntarily will become withdrawn from its fastening position in its groove. Operations in forest environment where a lot of brushwood is present are examples of a high risk for such involuntary release of the latch.
Thus requirements have been raised for a safe mounting stop/mounting latch/stop latch/security latch which can be used in such couplings and which can be readily released from its blocking position to allow a movement of the male-female parts further into each other to release the connecting blocking elements.